.cent{
    text-align: center;
}
.size{
    width: 50%;
    height: 400px;
}
li{
    list-style-type: none;
}
a{
    color: #000;
    text-decoration: none;
}
ul.inline-list{
    display: flex;/*设置为flex布局以便使用flex-wrap属性*/
    flex-wrap: nowrap;/*不换行*/
    list-style: none;/*去除项目符号*/
    margin: 0;/*去除外边框*/
    padding: 0;/*去除内边框*/
}
ul.inline-list li{
    margin-right: 10px;/*增加项间距*/
}